1. Field of the Invention
The present invention generally relates to rodent traps with folding spreader mechanisms and spring triggers, and in particular to traps with devices and methods for reducing friction in their operation by maintaining proper alignments of the component parts.
2. Description of the Prior Art
There is a wide variety of rodent and especially gopher traps that have been marketed and patented over the years. Many of the rodent traps are not very effective because they require the rodent to climb over parts of the mechanisms in order to reach a triggering device. And many of these triggers are not very sensitive and require significant force.
Fundamentally, gopher traps must fit into an ordinary sized gopher hole and be able to operate effectively within the confines of that hole. Traps that depend on arms closing down on the gopher when the trap is triggered must also apply enough force to kill the gopher rather than merely hold onto it. The triggers should be very sensitive, yet stable enough to prevent the trap from triggering prematurely.
When a gopher hole is left open and exposed, any resident gopher can be expected to come investigate and to try to close the hole at the surface with loose dirt. Typical gopher traps are fully inserted into these holes with their capturing arms pointed down into the hole and the hole is left open. It is this investigation behavior that will cause a gopher to come up between a trap's outstretched arms and trigger the spring closure.
One type of common gopher traps use two parallel opposite rotating shafts coupled closely together with rotating jaws at the ends. These are placed down into the gopher hole. The distal ends of each of these shafts have wide open half-nooses that can be triggered to forcefully close on a hinge together to snare and kill the gopher. The problem with these mechanisms is the gopher must crawl over the length of the oppositely rotating shafts, couples, and supporting mechanisms, to reach the trigger.
A better, but still conventional type of gopher trap is like that described by Oscar Johnson, et al., in U.S. Pat. No. 4,733,494, issued Mar. 29, 1988. A pair of elongated rods with jaws on the ends are biased closed together by a coil spring. A folding, over-center toggle trip mechanism is slipped on the rods between the coil spring and the jaws to lock them open. A trigger levers the over-center toggle trip mechanism past its over-center point, and spring pressure does the rest to fold up the toggle so the jaws can snap closed. The problem with this arrangement is caused by the toggle trip mechanism locking over center, too much pressure is needed on the trigger to activate the trap.
What is needed is an improved folding spreader mechanism for a trap with a trigger mechanism that does not go over-center and is sensitive to slight touches on the trigger.